The infantilisation of British society knows no bounds. We meek, vulnerable folk need the blunderbuss of the law to protect us from bad and dangerous speech – at all times. This could have only been the rationale behind the absurd original decision, and even more ridiculous upholding of that decision, to convict Paul Chambers for posting his infamous airport tweet in January 2010.

Now sanity has finally prevailed, with the trainee accountant, backed by an army of celebrities, persuading the high court to overturn the conviction.

To recap: Chambers had arrived at Robin Hood airport in South Yorkshire on 6 January 2010 hoping to fly to Belfast to meet his girlfriend, whom he had met on Twitter. On finding the airport closed by snow, he tweeted: "Crap! Robin Hood Airport is closed. You've got a week and a bit to get your shit together otherwise I am blowing the airport sky high!!"

Nothing happened. It should have been end of story. In their judgment published today, the three presiding judges provide a useful narrative. "There was no evidence before the crown court to suggest that any of the followers of the appellant's 'tweet', or indeed anyone else who may have seen the 'tweet' posted on the appellant's timeline, found it to be of a menacing character or, at a time when the threat of terrorism is real, even minimally alarming. In fact, nothing was done about it by anyone until 11 January 2010, some five days later, when the duty manager responsible for security at Robin Hood Airport, while off duty at home, found it."

That manager then alerted police. Incredibly, they arrested Chambers at his workplace, charging him under section 127(1) of the Communications Act, which prohibits sending "by means of a public electronic communications network a message or other matter that is grossly offensive or of an indecent, obscene or menacing character".

Imagine you really did want to blow up an airport. Some have done so in the past, and sadly others will try to do so in the future. Would you, if you wanted to maximise your prospects of success, flag it up in advance?

It can only be hoped that this judgment, delivered by the lord chief justice, Lord Judge, and two other senior legal figures, will introduce some sanity to the evolving legal framework surrounding social media.

Lord Judge and his colleagues have provided a useful definition of Twitter:

"'Tweets' include expressions of opinion, assertions of fact, gossip, jokes (bad ones as well as good ones), descriptions of what the user is or has been doing, or where he has been, or intends to go. Effectively it may communicate any information at all that the user wishes to send, and for some users, at any rate, it represents no more and no less than conversation without speech."

They are right on two vital points, hopefully setting legal precedent. Twitter is a place where brief observations about politics, world affairs and other weighty matters mingle with bad taste and crass remarks. A tweet should not be regarded as a published document as in a newspaper or mainstream website or blogpost.

Defining the line between these is admittedly difficult and subjective. It is not, however, beyond the wit of the police and courts to distinguish between direct incitement to violence and frustrated silliness.

The authorities are not solely to blame for this state of affairs. We the public, both Twitter-using and non-Twitter-using, have elevated taking offence to a human right. We see hurt and danger around every corner and lurking in every missive. For sure, some are beyond the pale. One or two might be prosecutable. But, for the most part we should develop a thicker skin, keep calm and carry on.